RESUMO
BACKGROUND: Coagulase-negative Staphylococcus species are an emerging cause of intramammary infection, posing a significant economic and public health threat. The aim of this study was to assess the occurrence of coagulase-negative Staphylococcus species in bovine milk and dairy farms in Northwestern Ethiopia and to provide information about their antibiotic susceptibility and virulence gene profiles. METHODS: The cross-sectional study was conducted from February to August 2022. Coagulase-negative Staphylococcus species were isolated from 290 milk samples. Species isolation and identification were performed by plate culturing and biochemical tests and the antimicrobial susceptibility pattern of each isolate was determined by the Kirby-Bauer disc diffusion test. The single-plex PCR was used to detect the presence of virulent genes. The STATA software version 16 was used for data analysis. The prevalence, proportion of antimicrobial resistance and the number of virulent genes detected from coagulase-negative Staphylococcus species were analyzed using descriptive statistics. RESULTS: Coagulase-negative Staphylococcus species were isolated in 28.6%, (95% CI: 23.5-34.2) of the samples. Of these, the S. epidermidis, S. sciuri, S. warneri, S. haemolyticus, S. simulans, S. chromogens, S. cohnii, and S. captis species were isolated at the rates of 11, 5.2, 3.4, 3.1, 3.1, 1, 1, and 0.7% respectively. All the isolates showed a high percentage (100%) of resistance to Amoxicillin, Ampicillin, and Cefotetan and 37.5% of resistance to Oxacillin. The majority (54.2%) of coagulase-negative isolates also showed multidrug resistance. Coagulase-negative Staphylococcus species carried the icaD, pvl, mecA, hlb, sec, and hla virulent genes at the rates of 26.5%, 22.1%, 21.7%, 9.6%, 9.6% and 8.4% respectively. CONCLUSION: The present study revealed that the majority of the isolates (54.2%) were found multidrug-resistant and carriage of one or more virulent and enterotoxin genes responsible for intramammary and food poisoning infections. Thus, urgent disease control and prevention measures are warranted to reduce the deleterious impact of coagulase-negative species. To the best of our knowledge, this is the first study in Ethiopia to detect coagulase-negative Staphylococcus species with their associated virulent and food poisoning genes from bovine milk.
Assuntos
Antibacterianos , Coagulase , Testes de Sensibilidade Microbiana , Leite , Staphylococcus , Animais , Leite/microbiologia , Bovinos , Staphylococcus/genética , Staphylococcus/efeitos dos fármacos , Staphylococcus/isolamento & purificação , Staphylococcus/enzimologia , Etiópia , Coagulase/genética , Coagulase/metabolismo , Estudos Transversais , Antibacterianos/farmacologia , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/veterinária , Virulência/genética , Fatores de Virulência/genética , Feminino , Genes Bacterianos/genética , Mastite Bovina/microbiologiaRESUMO
Methicillin-resistant Staphylococcus aureus (MRSA) constitutes an important cause for concern in the field of public health, and the role of the food chain in the transmission of this pathogen and in antimicrobial resistance (AMR) has not yet been defined. The objectives of this work were to isolate and characterize coagulase-positive Staphylococcus (CoPS) and coagulase-negative Staphylococcus (CoNS), particularly S. aureus, from school dining rooms located in Argentina. From 95 samples that were obtained from handlers, inert surfaces, food, and air in 10 establishments, 30 Staphylococcus strains were isolated. Four isolates were S. aureus, and the remaining ones (N = 26) belonged to 11 coagulase-negative species (CoNS). The isolates were tested for susceptibility to nine antibiotics. The presence of genes encoding toxins (luk-PV, sea, seb, sec, sed, and see), adhesins (icaA, icaD), and genes that confer resistance to methicillin (mecA) and vancomycin (vanA) was investigated. The resistance rates measured for penicillin, cefoxitin, gentamicin, vancomycin, erythromycin, clindamycin, levofloxacin, trimethoprim-sulfamethoxazole, and tetracycline were 73%, 30%, 13%, 3%, 33%, 17%, 13%, 7%, and 7% of the isolates, respectively. Seventeen AMR profiles were detected, and 11 isolates were multidrug resistant (MDR). Seven methicillin-resistant Staphylococcus isolates were detected in the hands of handlers from four establishments, two of them were MRSA. Two S. aureus isolates presented icaA and icaD, another one, only icaD. The gene vanA was found in two isolates. In relation to S. aureus, resistance to vancomycin but not to gentamicin was detected. School feeding plays a key role in the nutrition of children, and the consumption of food contaminated with MRSA and vancomycin-resistant S. aureus (VRSA) can be a serious threat to health. In particular, it was detected that the handlers were the source of MRSA, VRSA, MR-CoNS (methicillin-resistant coagulase-negative Staphylococcus), and MDR isolates. The results obtained indicate that the vigilance of this pathogen in school dining rooms should be extreme.
Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Criança , Humanos , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus , Coagulase/genética , Vancomicina , Argentina , Infecções Estafilocócicas/epidemiologia , Testes de Sensibilidade Microbiana , Staphylococcus/genética , Antibacterianos/farmacologia , Instituições Acadêmicas , GentamicinasRESUMO
PURPOSE: To compare the effect of povidone-iodine (PI) 5% and moxifloxacin 0.5% solutions versus PI 5% solution alone on the conjunctival bacterial flora. METHODOLOGY: This is a comparative study in which the study population comprised adult patients scheduled for elective small incision cataract surgery. The eye to be operated (control eye) received topical moxifloxacin 0.5% drops 4 times, 1 day before surgery and 2 applications on the day of surgery. As placebo, the contralateral eye (study eye) received saline 0.90% drops as per the same schedule. Before surgery, on table, PI 5% was instilled in the conjunctival sac in both eyes. Conjunctival swabs were taken before initiation of therapy and 3 min after instillation of PI. RESULTS: Of the 96 pairs of eyes included in the study, conjunctival cultures before prophylaxis were similar between the two groups (p = 0.31), with 54 samples (56%) of the study group and 49 (51%) of the control group showing growth. With positive cultures reducing to 7 (14%) in the study group and 8 (16%) in the control group, both the prophylaxis methods appeared equally efficacious (p = 0.79). Both the groups showed a significant reduction in positive cultures following prophylaxis (p < 0.0001). CONCLUSIONS: PI 5% alone as preoperative prophylaxis was as effective as its combination therapy with moxifloxacin 0.5% in the reduction in conjunctival bacterial colonization.
Assuntos
Extração de Catarata , Povidona-Iodo , Adulto , Humanos , Moxifloxacina/farmacologia , Povidona-Iodo/uso terapêutico , Antibacterianos , Estudos Prospectivos , Túnica Conjuntiva , AntibioticoprofilaxiaRESUMO
BACKGROUND: Coagulase-negative staphylococci can cause hospital-acquired infections, especially in immunocompromised hosts. Bacterial meningitis is a potentially fatal infection of the central nervous system, causing high mortality and morbidity. In general, the causative agents of meningitis, coagulase-negative staphylococci, are associated with direct implantation of a foreign body and the presence of a cerebrospinal fluid (CSF) shunt. Here, we describe a case of nosocomial meningitis caused by Staphylococcus haemolyticus in a child with neutropenia who had no intracranial foreign devices. CASE PRESENTATION: A 15-year-old boy with relapsed acute myeloid leukemia undergoing chemotherapy through a central venous catheter developed fever on Day 13 post-initiation of chemotherapy. There was no history of implantation of neurosurgical devices. Two blood cultures obtained on Day 14 were positive for Staphylococcus haemolyticus. Clinical improvement was noted, and treatment with vancomycin and removal of the central venous catheter resulted in negative repeat blood cultures on Day 18. However, the patient developed a tendency for somnolence and improper speech, along with persistent fever on Day 26. A lumber puncture was performed on Day 27, resulting in positive culture of Staphylococcus haemolyticus. He was diagnosed with meningitis and the dosage of vancomycin was increased. A repeat CSF culture was positive for Staphylococcus haemolyticus on Day 40, so oral rifampicin was added. CSF findings on Day 46 revealed a low concentration of vancomycin, and treatment was switched from vancomycin plus rifampicin to linezolid. After Day 46, four subsequent cerebrospinal fluid tests of the CSF showed no growth of Staphylococcus haemolyticus. The patient's symptoms were improved on Day 52. Brain and spinal magnetic resonance images was taken and it showed no abnormalities. Linezolid was continued until Day 72. The patient was discharged without any complications on Day 72. CONCLUSIONS: To the best of our knowledge, this is the first reported case of Staphylococcus haemolyticus meningitis in a patient without a neurosurgical device. Typical symptoms or signs may be absent in a patient with meningitis who also has neutropenia. Repeated tests of the CSF, and prolonged duration of antibiotics should be considered if atypical pathogens are detected in immunocompromised hosts.
Assuntos
Infecção Hospitalar , Meningites Bacterianas , Neutropenia , Infecções Estafilocócicas , Masculino , Humanos , Criança , Adolescente , Linezolida/uso terapêutico , Vancomicina/uso terapêutico , Staphylococcus haemolyticus , Infecção Hospitalar/microbiologia , Rifampina/uso terapêutico , Coagulase , Antibacterianos/uso terapêutico , Staphylococcus , Neutropenia/complicações , Meningites Bacterianas/complicações , Meningites Bacterianas/diagnóstico , Meningites Bacterianas/tratamento farmacológico , Hospitais , Infecções Estafilocócicas/complicações , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/tratamento farmacológicoRESUMO
To contribute to the treatment decision and optimize coagulase-negative staphylococcus (CNS) control programs, we conducted a meta-analysis to investigate the epidemiology and antimicrobial resistance rates of coagulase-negative staphylococcus associated with bovine mastitis in China. Three databases (PubMed, Google scholar and China National Knowledge Infrastructure database) were utilized to obtain relevant publications. A total of 18 publications were included in our research, and 3 of them included antimicrobial resistant (AMR) test. The pooled prevalence of coagulase-negative staphylococcus was 17.28%. Subgroup analysis revealed that the prevalence was higher in South China than in North China, was higher in 2011-2020 than in 2000-2010 and was higher in clinical bovine mastitis cases than in subclinical cases. The pooled AMR were most resistant to ß-lactams, followed by tetracyclines, quinolones, nitrofurans, lincosamides, sulfonamides, amphenicol and aminoglycosides. The pooled AMR rate of coagulase-negative staphylococcus was lower in 2011-2020 than in 2000-2010. Although the prevalence of CNS showed an increasing trend over 20 years, the AMR rate showed a decreasing trend, and the clinical type of mastitis was the most frequent and the prevalence was highest in South China. Finally, CNS was most resistant to ß-lactams amongst the eight groups of antimicrobial agents.
Assuntos
Doenças dos Bovinos , Mastite Bovina , Infecções Estafilocócicas , Bovinos , Feminino , Animais , Antibacterianos/farmacologia , Coagulase , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/veterinária , Mastite Bovina/tratamento farmacológico , Mastite Bovina/epidemiologia , Prevalência , Farmacorresistência Bacteriana , Staphylococcus , beta-Lactamas , Testes de Sensibilidade Microbiana/veterináriaRESUMO
PURPOSE: The objective of this study was to investigate the molecular characteristics and potential resistance mechanisms of linezolid-resistant (LZR) Staphylococcus capitis isolates from a tertiary hospital in China. METHODS: S. capitis isolates were obtained from clinical patient specimens; three of the isolates came from blood cultures and one from the hydrothorax. The agar dilution and E-test methods were used to identify antibiotic resistance. The chloramphenicol-florfenicol resistance (cfr) gene carrier status of the strains was determined by PCR. Whole-genome sequencing (WGS) was used to identify point mutations and L3, L4, and L22 mutations and to study the genetic environment of the cfr gene and the relationships between strains. RESULTS: The 4 isolates obtained in this study were all linezolid-resistant Staphylococcus strains. A similar of susceptibility profile pattern was observed in all four S. capitis strains, each of which exhibited a multidrug-resistant phenotype. A potentially novel mutation, C2128T, was identified, and the cfr genes of S. capitis strains were all positive. Additionally, the same mutations (C2128T and G2600T) were identified in all 23S rRNA sequences of the isolates, whereas mutations were lacking in the L3, L4, and L22 ribosomal proteins. The genetic environments surrounding cfr were identical in all four isolates. A schematic diagram of the phylogenetic tree showed that they were closely related to AYP1020, CR01, and TW2795, and a total of seven drug resistance genes were identified in these strains. CONCLUSIONS: The study indicated that the resistance of the Staphylococcus capitis strains to linezolid was caused by multiple mechanisms, and a potential novel mutation, C2128T, that may have an impact on bacterial resistance was identified.
Assuntos
Farmacorresistência Bacteriana , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Staphylococcus capitis , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Genes de RNAr , Humanos , Linezolida/farmacologia , Staphylococcus aureus Resistente à Meticilina/genética , Testes de Sensibilidade Microbiana , Mutação , Filogenia , RNA Ribossômico 23S/genética , Infecções Estafilocócicas/microbiologia , Staphylococcus capitis/genéticaRESUMO
Isolation of coagulase-negative Staphylococci (CoNS) in urine cultures of children is usually considered a contamination of the sample, except for Staphylococcus saprophyticus in older children. The aim of this study was to describe the characteristics of children in whom CoNS was considered a true urinary pathogen. The medical records of all children aged 0 to 18 years at Shaare Zedek Medical Center between 2013 and 2020 who were diagnosed with CoNS urinary tract infection (UTI) were reviewed for demographic, clinical, and laboratory data. CoNS were identified as the causative organism of UTIs in 30 children, none of whom was bacteremic. Male sex, younger age, and infection with non-S. saprophyticus CoNS were associated with higher risk of pyelonephritis in comparison to cystitis. Eleven (37%) children had previously known or newly diagnosed underlying urinary tract abnormalities. All patients recovered. CoNS were found to be an uncommon urinary pathogen among children but can cause pyelonephritis, especially in young children and in males.Conclusion: The finding of CoNS pyelonephritis requires thorough search for urinary abnormalities.
Assuntos
Pielonefrite , Infecções Estafilocócicas , Infecções Urinárias , Sistema Urinário , Adolescente , Criança , Pré-Escolar , Coagulase , Humanos , Lactente , Recém-Nascido , Masculino , Pielonefrite/diagnóstico , Infecções Estafilocócicas/complicações , Infecções Estafilocócicas/diagnóstico , Staphylococcus , Infecções Urinárias/complicações , Infecções Urinárias/diagnósticoRESUMO
BACKGROUND: Coagulase-negative staphylococci (CoNS) are biofilm-producing pathogens whose role in periprosthetic joint infection (PJI) is increasing. There is little data on the prognosis and treatment considerations in the setting of PJI. We sought to evaluate the clinical characteristics, outcomes, and complications in these patients. METHODS: This is a retrospective cohort study of adult patients at a single tertiary medical center from 2009 to 2020 with culture-proven CoNS PJI after total knee arthroplasty, as diagnosed by Musculoskeletal Infection Society criteria. The primary outcome was treatment success, with failure defined as recurrent CoNS PJI, recurrent PJI with a new pathogen, and/or chronic oral antibiotic suppression at one year postoperatively. RESULTS: We identified 55 patients with a CoNS total knee arthroplasty PJI with a mean follow-up of 29.8 months (SD: 16.3 months). The most commonly isolated organism was Staphylococcus epidermidis (n = 36, 65.5%). The overall prevalence of methicillin resistance was 63%. Surgical treatment included surgical debridement, antibiotics, and implant retention in 25 (45.5%) cases and two-stage revision (22 articulating and eight static antibiotic-impregnated spacers). At one-year follow-up, only 47% of patients had successful management of their infection. The surgical debridement, antibiotics, and implant retention cohort had the higher rate of treatment failure (60.0%) compared to two-stage revision (46.7%). CONCLUSION: These results indicate a poor rate of success in treating CoNS PJI. This likely represents the interplay of inherent virulence through biofilm formation and decreased antibiotic efficacy.
Assuntos
Artrite Infecciosa , Infecções Relacionadas à Prótese , Adulto , Antibacterianos/uso terapêutico , Artrite Infecciosa/etiologia , Coagulase/uso terapêutico , Desbridamento/métodos , Humanos , Infecções Relacionadas à Prótese/epidemiologia , Infecções Relacionadas à Prótese/etiologia , Infecções Relacionadas à Prótese/terapia , Estudos Retrospectivos , Staphylococcus , Resultado do TratamentoRESUMO
BACKGROUND: Exotoxins secreted from Staphylococcus aureus or Streptococcus pyogenes act as superantigens that induce systemic release of inflammatory cytokines and are a common cause of toxic shock syndrome (TSS). However, little is known about TSS caused by coagulase-negative staphylococci (CoNS) and the underlying mechanisms. Here, we present a rare case of TSS caused by Staphylococcus simulans (S. simulans). CASE PRESENTATION: We report the case of a 75-year-old woman who developed pneumococcal pneumonia and bacteremia from S. simulans following an influenza infection. The patient met the clinical criteria for probable TSS, and her symptoms included fever of 39.5 °C, diffuse macular erythroderma, conjunctival congestion, vomiting, diarrhea, liver dysfunction, and disorientation. Therefore, the following treatment was initiated for bacterial pneumonia complicating influenza A with suspected TSS: meropenem (1 g every 8 h), vancomycin (1 g every 12 h), and clindamycin (600 mg every 8 h). Blood cultures taken on the day after admission were positive for CoNS, whereas sputum and pharyngeal cultures grew Streptococcus pneumoniae (Geckler group 4) and methicillin-sensitive S. aureus, respectively. However, exotoxins thought to cause TSS, such as TSS toxin-1 and various enterotoxins, were not detected. The patient's therapy was switched to cefazolin (2 g every 8 h) and clindamycin (600 mg every 8 h) for 14 days based on microbiologic test results. She developed desquamation of the fingers on hospital day 8 and was diagnosed with TSS. Conventional exotoxins, such as TSST-1, and S. aureus enterotoxins were not detected in culture samples. The serum levels of inflammatory cytokines, such as neopterin and IL-6, were high. CD8+ T cells were activated in peripheral blood. Vß2+ population activation, which is characteristic for TSST-1, was not observed in the Vß usage of CD8+ T cells in T cell receptor Vß repertoire distribution analysis. CONCLUSIONS: We present a case of S. simulans-induced TSS. Taken together, we speculate that no specific exotoxins are involved in the induction of TSS in this patient. A likely mechanism is uncontrolled cytokine release (i.e., cytokine storm) induced by non-specific immune reactions against CoNS proliferation.
Assuntos
Síndrome da Liberação de Citocina/complicações , Choque Séptico/complicações , Infecções Estafilocócicas/complicações , Staphylococcus aureus/isolamento & purificação , Staphylococcus/isolamento & purificação , Streptococcus pneumoniae/isolamento & purificação , Idoso , Antibacterianos/administração & dosagem , Hemocultura , Cefazolina/administração & dosagem , Clindamicina/administração & dosagem , Síndrome da Liberação de Citocina/tratamento farmacológico , Citocinas/sangue , Feminino , Humanos , Testes de Sensibilidade Microbiana , Choque Séptico/tratamento farmacológico , Escarro/microbiologia , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Resultado do TratamentoRESUMO
PURPOSE: Even though prosthetic valve endocarditis due to coagulase-negative staphylococci (CoNS) is widely documented and attracts global attention, native valve endocarditis due to CoNS has been also described lately and may warrant closer attention due to the relative increased incidence. METHODS: We describe a 35-year-old male patient who is a former resident of a long-term health-care facility with multiple co-morbidities, diagnosed with native aortic valve S. capitis endocarditis and underwent conservative antimicrobial treatment with full recovery and no recurrence after 6 months' follow-up. In addition, we reviewed the English literature on all reported cases of S. capitis endocarditis. RESULTS: Infective endocarditis due to S. capitis has thus far been described in 13 patients. All but three had involved native valves with two infected prosthetic valves and a single case of infection in an implanted transvenous pacemaker. Although the number of cases of endocarditis due to S. capitis is small, early removal of either a prosthetic valve or infected pacemaker would appear prudent, while native valve endocarditis could successfully be treated with appropriate antimicrobials alone. CONCLUSIONS: Staphylococcus capitis is classified as coagulase-negative staphylococci with the inherent ability to cause debilitating native valve endocarditis and is usually managed conservatively.
Assuntos
Endocardite Bacteriana/terapia , Infecções Estafilocócicas/terapia , Staphylococcus capitis/fisiologia , Adulto , Endocardite Bacteriana/tratamento farmacológico , Endocardite Bacteriana/microbiologia , Endocardite Bacteriana/cirurgia , Humanos , Masculino , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/cirurgiaRESUMO
BACKGROUND: Indwelling central venous catheters (CVC) are used to provide long term hemodialysis. The commonest and the severe complication of CVC is the central line-associated bloodstream infection (CLABSI). This study was done to assess the etiology and infectious complications of CVC in children on long term hemodialysis. METHODS: Children newly undergoing hemodialysis and having indwelling CVC were included. They were followed up to a period of 2-years to assess infectious complications. Catheter bundle care approach was employed to prevent infections and other complications. Automated culture from the central catheter and peripheral vein and 2D echocardiography were done in each hemodialysis. Serial procalcitonin (PCT) was measured. Differential time of positivity (DTP) was used to detect CLABSI. During homestay in weekly telephone conversations were done to assess features of infection, and whenever having, we have asked to admit to the tertiary care unit. Logistic regression was performed, and the significant outcome variable was considered following multivariable analysis as a risk factor. RESULTS: Blood cultures were positive in 1090 (74.5%) out of 1462 children. According to DTP, 410 (28%) were having CLABSI, while 520 (35.6%) were having bacteremia without CLABSI. Out of 410 CLABSI patients, 79 (19.2%) were asymptomatic. Coagulase-negative Staphylococcus spp. (CoNS) bacteremia was significantly associated with asymptomatic CLABSI. Right-sided infective endocarditis (RS-IE) was significantly associated with asymptomatic CLABSI and asymptomatic bacteremia without CLABSI. CoNS was associated significantly in RS-IE following asymptomatic CLABSI and asymptomatic bacteremia. PCT was in asymptomatic CLABSI was 1.8 ± 0.9 ng/mL while in symptomatic CLABSI was 11.3 ± 2.5 ng/ml (P = 0.02). CoNS bloodstream infection, tunneled CVC, peripherally inserted central catheter, femoral site, the number of line days > 90, receipt of vancomycin, meropenem, or linezolid in the 5 days before CLABSI diagnosis and recurrent bacteremia were risk factors for asymptomatic CLABSI. CONCLUSIONS: Asymptomatic CLABSI could be a rare occurrence. CoNS was predominantly isolated in patients with asymptomatic CLABSI. RS- IE is a well-known complication in long term indwelling CVC. CoNS was significantly associated with RS-IE following asymptomatic CLABSI. Regular procalcitonin, microbiological, and imaging studies would be essential to detect infectious complications in both symptomatic and asymptomatic patients implanted with long term indwelling CVCs.
Assuntos
Doenças Assintomáticas , Bacteriemia/etiologia , Infecções Relacionadas a Cateter/diagnóstico , Cateterismo Venoso Central/efeitos adversos , Cateteres de Demora/microbiologia , Cateteres Venosos Centrais/microbiologia , Infecção Hospitalar/diagnóstico , Infecções Estafilocócicas/diagnóstico , Staphylococcus aureus/isolamento & purificação , Antibacterianos/uso terapêutico , Bacteriemia/tratamento farmacológico , Infecções Relacionadas a Cateter/sangue , Infecções Relacionadas a Cateter/tratamento farmacológico , Infecções Relacionadas a Cateter/microbiologia , Criança , Pré-Escolar , Coagulase/metabolismo , Infecção Hospitalar/sangue , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/microbiologia , Endocardite/etiologia , Feminino , Seguimentos , Hospitais de Ensino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Fatores de Risco , Sri Lanka , Infecções Estafilocócicas/sangue , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/enzimologiaRESUMO
AIM: Detection of coagulase-negative Staphylococcus in blood culture may be a result of either bacteremia or contamination. This often leads to diagnostic uncertainly. Our objective was to develop a method for differentiating whether a coagulase-negative Staphylococcus sp. positive blood culture represents bacteremia or contamination based on positive bottle detection pattern and time to positivity (TTP). METHODS: This study included 155 and 51 adults with positive blood cultures for Staphylococcus epidermidis and Staphylococcus hominis, respectively, over a three-year period from 2016 to 2018. Positive blood culture cases were categorized as either bacteremia or contamination based on the clinically available information, and the detection pattern and TTP in each category were investigated. RESULTS: A total of 57, 92, and 6 S. epidermidis positive blood cultures were categorized as bacteremia, contamination, and undetermined, respectively, whereas 15 and 36 S. hominis positive blood cultures were categorized as bacteremia and contamination, respectively. For positive blood cultures categorized as bacteremia, all four bottles in two sets of blood cultures were positive in 47/47 S. epidermidis and 14/14 S. hominis, respectively, whereas either one bottle in each of two sets or three bottles in two sets were positive in 10/19 S. epidermidis and 1/4 S. hominis, respectively; most of those TTPs were <48 h. Among them, the TTP in catheter-related blood stream infection was <24 h. CONCLUSION: Although clinical assessment is crucial to differentiate between bacteremia and contamination, a combination of positive bottle detection pattern and TTP is a valuable diagnostic auxiliary tool.
Assuntos
Bacteriemia/diagnóstico , Hemocultura/estatística & dados numéricos , Infecções Relacionadas a Cateter/diagnóstico , Infecções Estafilocócicas/diagnóstico , Staphylococcus epidermidis/isolamento & purificação , Staphylococcus hominis/isolamento & purificação , Adulto , Bacteriemia/microbiologia , Hemocultura/instrumentação , Hemocultura/normas , Infecções Relacionadas a Cateter/sangue , Contaminação de Equipamentos/prevenção & controle , Contaminação de Equipamentos/estatística & dados numéricos , Humanos , Valor Preditivo dos Testes , Estudos Retrospectivos , Manejo de Espécimes/instrumentação , Manejo de Espécimes/normas , Infecções Estafilocócicas/sangue , Infecções Estafilocócicas/microbiologiaRESUMO
OBJECTIVE: To evaluate the application value of time to positivity (TTP) for blood culture combined with inflammatory parameters that included immature granulocyte percentage (IG%), immature granulocyte count (IG#), C-reactive protein (CRP), white blood cells (WBC) neutrophil percentage (NE%), and neutrophil-to-lymphocyte ratio (NLR), and to identify bloodstream infections from contamination with coagulase-negative staphylococci (CoNS) in pediatric patients. METHODS: Data of 12 897 inpatients with blood culture CoNS were retrospectively collected and analyzed from January-December 2019 at our hospital. According to pre-defined criteria, they were divided into a CoNS infection group (132 cases) and a CoNS contamination group (124 cases). Infection with Staphylococcus aureus (SA, 27 cases) at the same period was considered a positive control group. ROC curve analysis assisted in determining the value of applying TTP combined with the above-mentioned inflammatory parameters to distinguish CoNS infection from contamination. RESULTS: Among the 256 strains of CoNS, Staphylococcus hominis (55.1%), Staphylococcus epidermidis (32.0%), and Staphylococcus capitis (7.0%) were common. There was no significant difference in the subspecies distribution between the infection and contamination groups. The TTP of the CoNS infection group was significantly lower than the contamination group (P < .05). IG%, IG#, CRP, NE%, and NLR were all higher in the infected group as compared to the contaminated group (P < .05), while WBC was similar among groups. There was also no statistical difference in those parameters when comparing the CoNS infection and SA groups. ROC analysis showed that TTP value in identifying CoNS infection from contamination was the highest with area under the curve (AUC) of 0.913, and the sensitivity and specificity were 0.827 and 0.852, respectively, at the optimal cutoff value of 23.9 hours. This was followed by IG% (AUC = 0.712), with an optimal critical value of 0.55%, and a sensitivity of 0.519 and specificity of 0.797. All the AUC values of IG#, CRP, NE%, and NLR were <0.7. A combination of TTP with IG%, CRP, and NLR improved the AUC, sensitivity, specificity, accuracy, PPV, and NPV values to 0.977, 0.922, 0.957, 91.8%, 92.2%, and 91.3%, respectively. CONCLUSIONS: TTP within 24 hours indicates likelihood of CoNS as the pathogenic agent in pediatric patient blood culture. The combination of TTP with IG% CRP and NLR might improve the diagnostic accuracy.
Assuntos
Bacteriemia/diagnóstico , Hemocultura , Proteína C-Reativa/análise , Contagem de Leucócitos , Infecções Estafilocócicas/diagnóstico , Bacteriemia/epidemiologia , Bacteriemia/microbiologia , Criança , Pré-Escolar , Feminino , Granulócitos/citologia , Humanos , Lactente , Masculino , Estudos Retrospectivos , Sensibilidade e Especificidade , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus/patogenicidade , Fatores de TempoRESUMO
BACKGROUND: Shoulder periprosthetic infections are predominantly caused by bacteria residing in the skin of healthy individuals. Knowledge of the factors associated with the loads of the different cutaneous bacteria in individuals having shoulder arthroplasty may help identify patients at higher risk of periprosthetic infection and help guide preventive measures. For this reason, we tested the hypothesis that easy-to-obtain preoperative characteristics were significantly associated with the cutaneous microbiology and the loads of specific bacteria in shoulders having joint replacement. METHODS: This study identified the microbiology of the unprepared epidermal skin surface and of the dermal edge freshly incised at surgery in 332 patients having primary shoulder arthroplasty. The load of bacteria in each sample was characterized as a value based on the laboratory report: 0 for "no growth"; 0.1 for "one colony only" or for "broth only"; and 1, 2, 3, and 4 for 1+, 2+, 3+, and 4+ growth, respectively. The relationships between preoperative patient characteristics and these semiquantitative results of the cutaneous cultures were analyzed. RESULTS: Cultures of the unprepared epidermal skin surface showed positive results for a wide variety of organisms, including Cutibacterium in 72%, coagulase-negative Staphylococcus in 61%, and a spectrum of other organisms in 32%. By contrast, cultures of the freshly incised dermal edge showed a great preponderance of Cutibacterium (34%) in comparison to low levels of coagulase-negative Staphylococcus (8%) and other organisms (2%). An increased dermal load of Cutibacterium was significantly associated with male sex, younger patient age, American Society of Anesthesiologists class 1, use of testosterone supplements, prior shoulder surgery, and higher Cutibacterium loads on the unprepared skin surface. CONCLUSIONS: Although the microbiology of the unprepared skin surface is diverse, the same is not true for the freshly incised dermis, where Cutibacterium is the predominant organism. Readily available preoperative patient characteristics are significantly associated with the load of Cutibacterium in the incised dermis. Preoperative cultures of the unprepared skin surface appear to be a new method for predicting the type and load of bacteria found in the freshly incised dermis at the time of surgery. Additional studies are needed to determine whether preoperative cultures of the unprepared epidermal skin surface can provide a method for identifying patients at increased risk of shoulder periprosthetic infections.
Assuntos
Artroplastia do Ombro/efeitos adversos , Epiderme/microbiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Propionibacteriaceae/isolamento & purificação , Infecções Relacionadas à Prótese/microbiologia , Estudos Retrospectivos , Fatores de Risco , Staphylococcus/isolamento & purificação , Adulto JovemRESUMO
The antibiotic resistance among coagulase - negative Staphylococcus (CoNS) species towards methicillin is rarely reported in veterinary medicine. Under the aspect/concept of One Health, those strains pose a risk to human health due to the presence in canine pets where the transfer of resistant genetic markers might occur to other staphylococci species. The aim of this study was to investigate the antimicrobial resistance pattern among Coagulase Negative Staphylococci (CoNS) isolated from asymptomatic dogs and those affected by topic infections. Swabs from 254 dogs were first seeded in Mannitol Salt Agar. Species identification was conducted by Matrix Assisted Laser Desorption ionization - time of flight (MALDI-TOF ms) as previously described. The susceptibility test was performed by disk diffusion according to CLSI standards. Detection of mecA gene was performed. CoNS could be recovered from both groups of dogs and an alarming presence of methicillin-resistant coagulase negative staphylococci (MRCoNS) was confirmed, in 10.2% (17/166) of the samples. Eight of those methicillin resistant strains were isolated from asymptomatic dogs whereas nine were present in dogs affected by pyoderma and otitis externa.
Assuntos
Coagulase/deficiência , Reservatórios de Doenças/microbiologia , Doenças do Cão/microbiologia , Resistência a Meticilina , Infecções Estafilocócicas/veterinária , Staphylococcus/isolamento & purificação , Animais , Antibacterianos/farmacologia , Doenças do Cão/transmissão , Cães , Farmacorresistência Bacteriana , Genes Bacterianos , Humanos , Resistência a Meticilina/genética , Testes de Sensibilidade Microbiana , Proteínas de Ligação às Penicilinas , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/transmissão , Staphylococcus/classificação , Staphylococcus/enzimologia , Staphylococcus/genéticaRESUMO
CoNS is the main cause of catheter-related bloodstream infections (CRBSI). Current guidelines recommend catheter withdrawal followed by antibiotics for at least 5 days. We aimed to assess the efficacy and safety of a shorter course of antibiotherapy in patients with CoNS CRBSI. All proven cases of CoNS CRBSI at our institution (Jan 12/Dec 17) were retrospectively analysed. Comparison of clinical characteristics and outcomes between patients receiving a short (SC ≤ 3 days) versus long antibiotic course (LC > 3 days) was performed. Cox regression models predicting the risk for complications (including propensity score [PS] for treatment assignment as covariate) were designed to adjust baseline differences among both treatment groups. A total of 79 cases were included. Most patients (75.9%) showed clinical response at day 7 after catheter removal. Complications occurred in 3.8% (three cases of septic thrombophlebitis) with no cases of endocarditis. Microbiological relapse (MR) occurred in 13 patients (16.5%). SC and LC were administered to 25 (31.6%) and 54 (68.4%) patients, respectively, with no significant differences in MR-free survival between SC and LC groups (87.8 vs 86.3%; P = 0.6). In PS-adjusted Cox regression analyses, a tunnelled catheter as the source of CRBSI was the only independent risk factor for MR (hazard ratio, 5.71; 95% confidence interval, 1.6-21) whereas the duration of therapy had no apparent impact. Shortening antibiotic therapy to ≤ 3 days is not associated with a poorer outcome or a greater risk of MR in patients with CoNS CRBI with catheter withdrawal.
Assuntos
Antibacterianos/uso terapêutico , Bacteriemia/tratamento farmacológico , Infecções Relacionadas a Cateter/tratamento farmacológico , Remoção de Dispositivo , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus/isolamento & purificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Bacteriemia/microbiologia , Infecções Relacionadas a Cateter/microbiologia , Cateteres Venosos Centrais/efeitos adversos , Criança , Coagulase/deficiência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Infecções Estafilocócicas/microbiologia , Staphylococcus/enzimologia , Fatores de Tempo , Resultado do Tratamento , Adulto JovemRESUMO
The aim of the study was to investigate the concentrations of acute-phase inter-α-trypsin inhibitor heavy chain 4 (ITIH4) in serum and milk of cows with subclinical mastitis caused by Streptococcus spp. (STR) and coagulase-negative Staphylococcus spp. (CNS) and healthy cows. The blood and milk samples were obtained from 60 mid-lactation, multiparous Holstein-Friesian cows from 7 herds in the Lublin region of Poland. In the milk samples from 40 cows with subclinical mastitis, Streptococcus spp. and CNS were isolated. The ITIH4 was significantly higher in serum of cows with subclinical mastitis caused both by STR and CNS compared with healthy cows. One hundred percent of animals infected with Streptococcus spp. and 89% of animals infected with Staphylococcus spp. showed ITIH4 concentration in sera higher than 0.5 mg/mL. The concentration of ITIH4 in milk also was significantly higher in cows with subclinical mastitis caused by Streptococcus spp. and Staphylococcus spp. compared with the control group. Seventy percent of cows infected by STR and CNS showed ITIH4 concentration in milk higher than 2.5 µg/mL. Milk ITIH4 concentration higher than 5 µg/mL was found in 55% of animals infected with Streptococcus spp. and in 40% of animals infected with Staphylococcus spp. No statistically significant differences were observed in ITIH4 concentrations both in serum and in milk between the studied unhealthy animal groups. These results suggest that ITIH4 may be used in the future as a novel diagnostic marker in serum and in milk of subclinical mastitis in cows.
Assuntos
alfa-Globulinas/análise , Mastite Bovina/sangue , Leite/química , Infecções Estafilocócicas/veterinária , Infecções Estreptocócicas/veterinária , alfa-Globulinas/metabolismo , Animais , Bovinos , Coagulase/análise , Coagulase/metabolismo , Feminino , Lactação , Mastite Bovina/microbiologia , Mastite Bovina/fisiopatologia , Leite/metabolismo , Polônia , Soro/química , Infecções Estafilocócicas/sangue , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/fisiopatologia , Staphylococcus/enzimologia , Staphylococcus/fisiologia , Infecções Estreptocócicas/sangue , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/fisiopatologia , Streptococcus/fisiologiaRESUMO
BACKGROUND: Diagnosing acute periprosthetic joint infection remains a challenge. Several studies have proposed different acute cutoffs resulting in the International Consensus Meeting recommending a cutoff of 100 mg/L, 10,000 cell/µL and 90% for serum C-reactive protein (CRP), synovial white blood cell count (WBC), and polymorphonuclear percentage (PMN%), respectively. However, establishing cutoffs are difficult as the control group is limited to rare early aseptic revisions, and performing aspiration in asymptomatic patients is difficult because of a fear of seeding a well-functioning joint arthroplasty. This study (1) assessed the sensitivity of current thresholds for acute periprosthetic joint infection (PJI) and (2) identified associated factors for false negatives. METHODS: We retrospectively reviewed patients with acute PJIs (n = 218), defined as less than 6 weeks from index arthroplasty, treated between 2000 and 2017. Diagnosis of PJI was based on 2 positive cultures of the same pathogen from the periprosthetic tissue or synovial fluid samples. Sensitivities of International Consensus Meeting cutoff values of CRP, synovial WBC, and PMN% were evaluated according to organism type. Multiple logistic regression analysis was performed to determine associated factors for false negatives. RESULTS: Overall, the sensitivity of CRP, synovial WBC, and PMN% for acute PJI was 55.3%, 59.6%, and 50.5%, respectively. Coagulase-negative Staphylococcus (CNS) demonstrated the lowest sensitivity for both CRP (37.5%) and WBC (55.6%). CNS infection was identified as an independent risk factor for false-negative CRP. CONCLUSIONS: Current thresholds for acute PJI may be missing approximately half of PJIs. Low virulent organisms, such as CNS, may be responsible for these false negatives. Current thresholds for acute PJI must be reexamined.
Assuntos
Artrite Infecciosa/cirurgia , Artroplastia de Quadril/efeitos adversos , Artroplastia do Joelho/efeitos adversos , Infecções Relacionadas à Prótese/diagnóstico , Líquido Sinovial/química , Idoso , Sedimentação Sanguínea , Proteína C-Reativa/análise , Coagulase , Testes Diagnósticos de Rotina , Feminino , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Infecções Relacionadas à Prótese/etiologia , Estudos Retrospectivos , Sensibilidade e Especificidade , Staphylococcus aureusRESUMO
A 61 year male, admitted in Combined Military Hospital Rawlpindi on 12th March 2017, operated for diverticulitis became colonized with Staphylococcus haemolyticus. Patient suffered repeated septic episodes caused by the same organism during his stay in hospital. The strain was identified as methicillin resistant Staphylococcus haemolyticus (MRSH) also resistant to Linezolid by analytical profile index for Staphylococcus (API Staph) and VITEK 2 Gram positive cocci panel. The isolate was cultured from blood cultures, Central Venous Catheter (CVC) tip and skin swabs. Patient was successfully treated with injectable vancomycin and skin decolonization was acheived with chlorhexidine bath after which no episode of MRSH infection occurred. Patient had an uneventful recovery and was discharged on 21st June. His follow up visit showed clinical improvement.